Manchester United pulled off what could potentially be one of the biggest transfers in the club's history. Not only because Juan Mata cost a club record fee, but also because he could potentially make a massive difference in United's run-in fortunes.

The Spanish midfielder is expected to take the place of Antonio Valencia in the first team as the club play host to Cardiff City on Tuesday evening.

The Red Devils are the favorites but there have been multiple instances that have seen United left looking exposed and vulnerable in the face of what on paper would be considered "lessor" competition.

While United will be welcoming a new face in Mata, they will see an old servant return as the newest leader of their opposition.

Ole Gunnar Solskjaer will return to Old Trafford for the first time in years. While he is likely to get a great reception, the fans will not tolerate their home side dropping any more points to club's that they believe they should be defeating.

With a gap to close on the group ahead of them, United have their work cut out for them to get back in the hunt for the top four and getting three points from the Bluebirds is their top priority.